Investigation on pressure fluctuation during parallel channel switching in fire-fighting

Abstract

Many large-flow fires need sustained and stable water supplies, which are often challenging because of the complex fire ground. To analyze the causes and influencing factors of pressure fluctuation in the process of switching water sources, an experimental setup and a simulation model were established. The basic hydraulics principle is that pressure drop occurs during the switching between two channels. The pressure drop magnitude in the main pipe was studied for various resistance values of the main pipe, switching time of the control valve in the channel, the number of parallel channels, and the diameter of the clustered pipe. The results show that three key parameters affect the magnitude of the pressure drop: a longer switching time, less pipe resistance, and more parallel channels can minimize the pressure drop magnitude of the mine pipe. This study provides fire equipment designer with information about the influence of different variables on the pressure drop magnitude of the main pipe and basic design criteria to minimize these effects. Meanwhile, a simple scheme is proposed to minimize the large pressure fluctuation, and the pressure fluctuation can be decreased and even eliminated to some extent.